ENVIRONMENTAL LIGHT AND RETINAL MEMBRANE DEVELOPMENT

环境光与视网膜膜发育

• 批准号: 3256366
• 负责人: DANIEL T ORGANISCIAK
• 金额: $ 13.36万
• 依托单位: WRIGHT STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-04-01 至 1989-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3256366
• 关键词: antioxidants; cell death; congenital vision disorder; dark adaptation; electron microscopy; high performance liquid chromatography; laboratory rat; light adaptations; light adverse effect; membrane lipids; membrane proteins; membrane structure; microscopy; monoclonal antibody; phosphoglycerides; radioassay; retina degeneration; retinal pigment epithelium; rhodopsin; rod cell; unsaturated fatty acids; visual photoreceptor; visual photosensitivity

Studies are proposed to continue and extend findings relevant to the pathological effects of visible light in retinal photoreceptor cells and in the retinal pigment epithelium (RPE) of rats. We will study the mechanism of light damage by determining the temporal sequence of antioxidative enzyme inactivation i n rod outer segments (ROS) isolated from light exposed rats and the loss od docosahexaenoic acid from ROS membranes. The protective effect of ascorbic acid on ROS enzymes and lipids will be measured in normal rats exposed to continuous light or to short light-dark periods and in ROS isolated at various times in the dark period following light exposure. Peroxidation of ROS membranes will be examined as the causative factor of light exposure. Peroxidation of ROS membranes will be examined as the causative factor of light damage by measureing the extent of rhodopsin loss and peroxide accumulation in the retinas of rats with depleted docosahexaenoic acid in their ROS. The protective effects of reduced ROS docosahexaenoate and ascorbate against light damage will be examined in combination, in rats, with the aim of further reducing, or eliminating, light damage to the retina. The same experimental paradigm of light exposures will be used to determine the sequence of photoreceptor cell and RPE cell membrane damage. Because of the differences in the extent of photoreceptor and RPE cell damage from light between cyclic light and dark reared normal rats and young and older dystrophic rats these will be our experimental animals. We will determine the extent of RPE cell membrane involvement during light damage by isolating RPE plasma membranes and measuring membrane enzymes and lipids. Both glass beads and bead-bound monoclonal antibodies against RPE plasma membrane proteins will be used to isolate the membranes from light damaged rats. Correlative light and electron microscopic studies will be performed on the eyes of light damaged rats. We will supply monoclonal antibodies by collaborative arrangement to begin functional studies of RPE plasma membrane protiens in normal and dystrophic rat RPE cells in tissue culture. Our studies in the temporal sequence of light damage in retina and between retina and RPE in the rat will provide insights into the mechanism of light damage in this model and can be extended to scorbutic animals in which ascorbate has also been shown to be protective. These studies are seen as being relevant to the prevention of light damage in the human eye, especially during periods of intense light exposure as occurs with increasing frequency in surgical settings and in the work place.

建议继续进行研究并扩展与以下相关的发现 可见光对视网膜感光细胞和视网膜的病理作用 大鼠视网膜色素上皮（RPE）。 我们将研究其机制 通过确定抗氧化的时间顺序来评估光损伤 光作用下杆外节 (ROS) 中的酶失活 暴露的大鼠和 ROS 膜中二十二碳六烯酸的损失。 这 抗坏血酸对 ROS 酶和脂质的保护作用 在暴露于连续光或短时间明暗的正常大鼠中进行测量 期间和在随后的黑暗期间的不同时间分离的ROS中 光照。 ROS 膜的过氧化将被检查为 光照的致病因素。 ROS膜的过氧化反应 通过测量程度来检查光损伤的原因 大鼠视网膜中视紫红质损失和过氧化物积累的影响 ROS 中的二十二碳六烯酸已耗尽。 的保护作用 减少ROS二十二碳六烯酸和抗坏血酸对抗光损伤 在大鼠中进行组合检查，目的是进一步减少，或 消除光线对视网膜的损伤。 相同的实验范式 曝光将用于确定感光器的顺序 细胞和RPE细胞膜损伤。 由于各方面的差异 循环光之间的光对感光器和视网膜色素上皮细胞造成的损伤程度 和黑暗饲养的正常大鼠以及年轻和年老的营养不良大鼠，这些将 成为我们的实验动物。 我们将确定 RPE 细胞的范围 通过隔离 RPE 质膜来参与光损伤期间的膜参与 并测量膜酶和脂质。 玻璃珠和珠绑定 针对 RPE 质膜蛋白的单克隆抗体将用于 将膜与光损伤的大鼠隔离。 相关光和 将对光损伤的眼睛进行电子显微镜研究 老鼠。 我们将通过合作安排提供单克隆抗体 开始对正常和正常人的 RPE 质膜蛋白进行功能研究 组织培养中营养不良的大鼠 RPE 细胞。 我们在时间上的研究 大鼠视网膜以及视网膜与 RPE 之间的光损伤序列 将深入了解该模型中的光损伤机制 可以扩展到坏血病动物，其中也显示了抗坏血酸 起到保护作用。 这些研究被认为与 防止人眼受到光损伤，尤其是在强光照射期间 随着手术频率的增加，强光照射会发生 设置和工作场所。